\documentclass{standalone}
\usepackage{tikz}
\usepackage{ctex,siunitx,ninecolors}
\setCJKmainfont{Noto Serif CJK SC}
\usepackage{tkz-euclide}
\usepackage{amsmath}
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\pgfdeclareverticalshading{pile}{100bp}{
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}
\begin{document}
\small
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\end{document}